Problem: ${4 \div 0.2 = {?}}$
$ {4 \div 0.2 = 4 \div \dfrac{2}{10}} $ $ {\phantom{4 \div 0.2} = 4 \div \dfrac{1}{5}} $ Dividing by a fraction is the same as multiplying by the reciprocal of the fraction. $ {4 \div \dfrac{1}{5} = 4 \times \dfrac{5}{1}} $ $ {\phantom{4 \div \dfrac{1}{5}} = 20} $